1. 01 Oct, 2009 1 commit
    • Linus Torvalds's avatar
      x86: Optimize cmpxchg64() at build-time some more · 982d007a
      Linus Torvalds authored
      Try to avoid the 'alternates()' code when we can statically
      determine that cmpxchg8b is fine. We already have that
      CONFIG_x86_CMPXCHG64 (enabled by PAE support), and we could easily
      also enable it for some of the CPU cases.
      
      Note, this patch only adds CMPXCHG8B for the obvious Intel CPU's,
      not for others. (There was something really messy about cmpxchg8b
      and clone CPU's, so if you enable it on other CPUs later, do it
      carefully.)
      
      If we avoid that asm-alternative thing when we can assume the
      instruction exists, we'll generate less support crud, and we'll
      avoid the whole issue with that extra 'nop' for padding instruction
      sizes etc.
      
      LKML-Reference: <alpine.LFD.2.01.0909301743150.6996@localhost.localdomain>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
      982d007a
  2. 30 Sep, 2009 36 commits
  3. 29 Sep, 2009 3 commits